Weight - Do you ask people? Is it ever an uncomfortable convo?

When you go up with someone (I'm not at that stage yet but curious), do you actually ask people what their weight is or do you just guess/approximate with your w&b calculations and get in the air?

Is it ever an uncomfortable conversation to have with friends/ those who want to fly with you???

I told someone the other day that I was flying microlights/light sport aircraft and she said that she wanted to come up one day when I have my licence. Quite insistent on it actually! But I was like ' yeah maybe 😬' .... yeah, I don't think putting such light a/c to their limits would be a great idea.